1. WYSIWG – not quite More than displayed information in files
Tracking changes – helps but may not be for final consumption
Metadata – information about data, document fingerprints
How do bits represent the original information?
Image and audio documents follow rules and arbitrary conventions (.doc, mp3, pdf, odt, etc.)
Modeling to rendering. Information is lost
Analog to digital, digital signal processing/editing (photoshop, remastering, etc.)
Sometimes not a model of anything in reality (virtual walk through)
Wikileaks, NSA Snowden (2013)
MP3 are compressed and quality is lost
ITEC 102

2. Is more sampling better?
pixels – picture elements
Raster and bitmap representations
Bits can represent different information
More bits per pixel can provide richer image/information, oversampling
Text vs. an image of text
Resolution of the device relates to quality
Compression – lossless and lossy
Temporal and spatial coherence allow compression
Processing power needed to reconstruct “on the fly” – video feeds
Technology life cycle – from records to MP3
Codecs, human can distinguish ~ 10M colors
ITEC 102

3. Data formats Protocols allow the transfer of bits
File formats – commercial vs. open (doc, odt, jpg, etc.)
Backward compatibility – hardware and software
Does data go away? – wiping a disk clean, data degradation
Hiding information
Steganography – sending messages in imperceptible ways
Cryptography – sending information in indecipherable ways
“state of the art” in technology is < 2 years
Preserving the web –
TCP/IP, net is not hardware as much as it is protocols
ITEC 102